var aaa = 'hello';
var aaabf = new Buffer(aaa);
console.log('hello的字符串长度：'+ aaa.length)
console.log('hello转成buffer后的字节长度：'+ aaabf.length)


var bbb = '你好';
var bbbbf = new Buffer(bbb);
console.log('你好的字符串长度：'+ bbb.length)
console.log('你好转成buffer后的字节长度：' +bbbbf.length)